These amazing Vietnamese sweet potato and prawn fritters (banh tom, which translates to prawn cake) are one of my favourite Vietnamese appetizers! These little bad boys are basically a prawn nestled in a basket of golden sweet potato strips, deep fried until crispy.
It is traditionally served with fresh lettuce, herbs and Vietnamese dipping sauce (nuoc mam cham). They are perfect when you want something a little different for the family or for guests at a dinner party.
Vietnamese Sweet Potato and Prawn Fritters (Banh Tom)
My family’s banh tom recipe is admittedly different to the authentic version. The main difference is we add minced dried shrimp to the batter. This came about when Scruff’s mum did not have any fresh prawns one day and used dried shrimp as a substitute. After that we experimented a bit and found the combination of dried and fresh shrimp dramatically increased the prawn flavour throughout the fritter. Since then we have not looked back.
Preparing the Dried Shrimp and Shrimp Water
Give the dried shrimp a good rinse, then soak in just-boiled water for 20 minutes. Once done, use a spoon to remove the dried shrimp and allow any impurities to settle at the bottom. Reserve 1 cup of the shrimp water, being careful not to pick up any impurities. If you accidentally throw out the shrimp water you can replace with plain water.
Pound the dried shrimp using either a pestle and mortar, food processor or similar.
Preparing the Sweet Potato
Cut the sweet potato into thin strips. If you make the strips too big they won’t crisp up as much when frying.
Combine the Ingredients in a Bowl
Add the batter ingredients, pounded shrimp and shrimp water in a mixing bowl and whisk. Once thoroughly combined, add the sweet potato and onion. Gently coat the potatoes with the batter, being careful not to break them.
Preparing the Prawns
Traditionally school prawns are used in banh tom since they are smaller and give better crunch. If you can’t get a hold of school prawns just substitute for another type of prawn.
We like to leave the prawn head on for looks but generally discard it before we eat. The shell is traditionally kept on for crunch and colour.
Of course if this is not to your taste then just peel, de-vein and de-head the prawns.
Shaping the Banh Tom
Here is our method for shaping the banh tom:
- Give the banh tom mixture a good stir to recoat the potatoes with batter.
- Take a large serving spoon and scoop out some of the potatoes.
- Use your fingers to shape / fan out the potato strips into a fritter shape.
- Spoon a little batter over the top of the potato strips.
- Dip the prawn into the batter, then place on top of the fritter.
Frying the Banh Tom
To fry these fritters you will need to fill a deep pan with at least 3 cm / 1.2 in of vegetable oil.
Then do the following:
- Bring your oil to roughly 170°C / 340°F. Do this before frying each batch.
- Slide the fritter into the oil to avoid splashing.
- Cook for roughly 2 minutes on each side or until golden.
- Remove and let them rest on a cooling rack for a few minutes.
- Don’t overcrowd the pan – we recommend frying no more than two fritters at a time. Each time you add a fritter, the oil temperature will drop, and you need hot oil to get the banh tom to crisp up.
- Longer cooking time – we recommend frying for 2 minutes on each side. The longer you fry the banh tom, the crispier it will be. Just be careful though because the sweet potato contains high amounts of sugar, which can burn quickly. If it is cooking to quickly then lower the temperature.
- Cool the fritters properly – as soon as you take them out of the oil place them on a cooling rack, allowing enough space between each one for air to circulate. Do not stack or overcrowd as any trapped steam will cause sogginess.
- Serve ASAP – They will soften over time.
How to Serve Banh Tom
Our family likes to eat banh tom by wrapping in lettuce leaves then dipping in Vietnamese dipping sauce (nuoc mam cham). You can also add Asian herbs like coriander and Thai basil for extra flavour.
This is how we plate up banh tom at home:
- Place the lettuces leaves, coriander and Thai basil on a large serving plate in the middle of the table.
- Give everyone a plate and a dipping bowl of Vietnamese dipping sauce.
- Place the fritters on a large plate.
- Everyone grab one and wrap away!
The Best Way to Reheat Banh Tom
Banh tom is best served immediately to ensure they stay crunchy. If you do need to reheat them, the best way is to use an air fryer. Heat the fritters at 180 C / 360 F for 5 minutes or until crispy. Do not stack them on top of each other.
If you don’t have an air fryer then use a grill instead.
Other Recipes You Might Like
- Deep Fried Crispy Spring Rolls (Cha Gio)
- Sticky Fish Sauce Wings in Air Fryer
- Vietnamese Banana and Coconut Pudding – Che Chuoi
- Vietnamese Crispy Crepes – Banh Xeo
- Quick Seafood and Garlic Linguine
These fritters are always a winner at my house and I highly recommend you try it out. I promise you won’t be disappointed!
Scruff & Steph
Banh Tom – Vietnamese Sweet Potato and Prawn Fritters
- 30 gm dried shrimp (optional but recommended and available at Asian grocers)
- 1.5 cups boiling water
- 350 gm sweet potato, peeled and cut into strips
- 1 small onion, thinly sliced
- 12 raw prawns with shell on
- vegetable oil for deep frying
- 1/3 cup self raising flour
- 1/3 cup glutinous rice flour
- 1/3 cup rice flour
- 1/2 tsp turmeric powder
- 1/4 tsp salt
- 1 cup reserved dried shrimp water or tap water
- 15 butter lettuce leaves or your choice
- Vietnamese dipping sauce
- Thai basil (optional)
- coriander (optional)
- If using dried shrimp, wash thoroughly in warm water then soak in a bowl with 1.5 cups of just-boiled water for 20 minutes.
- After 20 minutes, remove the soaking shrimp from the bowl with a spoon and save the water. Let the water settle so any impurities sink to the bottom. Carefully pour the shrimp water into a measuring cup leaving the impurities behind in the bowl.
- Pound the soaked shrimp in a mortar and pestle or blitz for 10 seconds in a small blender until minced.
- In a large mixing bowl, combine the dry ingredients, shrimp mince and the reserved shrimp water. Combine well (Note 1).
- Add the sweet potato strips and onions to the mixing bowl and gently stir. Leave aside.
- Prepare the prawns to your liking. We leave the prawn whole with the shell and head on (Note 2).
- Fill a deep pan on medium heat with 3-4 cm of vegetable oil. If you have a cooking thermometer, bring the oil temperature to roughly 170°C / 340°F.
- Before making a fritter, stir the mixture. With tongs, place the fritter mixture on a spatula or a big spoon and flatten it out.
- Coat the prawn in the batter and place it on top of the fritter.
- Slide the fritter off the spatula / spoon and into the oil (Note 3).
- Cook each fritter for roughly 2 mins on each side or until golden and crisp (Note 4).
- Remove the fritter and drain on a cooling rack. Do not let them cool on top of each other.
- Serve immediately.
- If you have accidentally thrown out the shrimp water just use tap water.
- We use the whole prawn because it looks more striking. We figure anyone who’s not comfortable with eating the heads or any other part can just pick it off.
- Do not overcrowd the pan with fritters. This is because the temperature of the oil will drop significantly and the fritters will absorb oil instead of developing that crunch.
- If the banh tom cooking too quickly without getting crispy then lower the temperature for the next batch.